1. Field of the Invention
The present invention relates to railcars for carrying slabs of various materials. More particularly, the present invention relates to a railcar for carrying steel slabs as well as steel coils. Most particularly, the present invention relates to a railcar for carrying steel slabs having an increased carrying capacity, easier loading and unloading, and having steel coil carrying capabilities.
2. Description of the Prior Art
Presently, steel slabs are often shipped on 52xe2x80x2-6xe2x80x3 Mill Gondola cars. The loading and unloading of the steel slabs from the Mill Gondola cars is not as sufficiently efficient as it might be. Large, heavy, cylindrical objects, and particularly coils of rolled steel, are also commonly transported on a flatcar or a troughed car. Either type of car has a cargo bed supported on a center sill or similar structure running the length of the car. The individual coils are chained or otherwise restrained in place. With regard to railcars designed specifically for carrying coils, the prior art is somewhat voluminous.
Known railcar arrangements for hauling coils of various materials are disclosed, for example, in U.S. Pat. Nos. 2,977,900; 3,009,426; 3,186,357; 3,291,072; 4,451,188; and 6,077,005.
U.S. Pat. No. 2,997,900 shows a railcar for transporting steel coils. A cover is used on a gondola car with cradles formed in the bottom of the car to retain the steel coils. The body of the gondola-car includes a narrow platform along the outer edge of the car.
U.S. Pat. No. 3,291,072 discloses a support system for carrying different sized coils. The outer support members are fixed at a downward slope. The two inner support members are hinged at both ends so that they can be inverted to divide a single large storage position into two smaller storage positions.
U.S. Pat. No. 3,186,357 shows a side sill and top flange arrangement. Planks extend the length of the car and extend at a downward angle from the side sills to a center sill. This forms a cradle that is an integral part of the car structure.
U.S. Pat. No. 3,009,426 shows a railcar for transporting steel coils that include a hinged cover to enclose the steel coils. Wooden planks run the length of the cradle and are bolted to angled members. The wooden planks define the surface of the trough, which engages the steel coil. The cover is split down the middle and is hinged at the outer edges. The cover rotates to permit coils to be loaded from the top or from the ends of the enclosure.
U.S. Pat. No. 4,451,188 shows a support deck with trough assemblies mounted on the support deck. The trough assemblies have a configuration that facilitates the mounting of various coil sizes. Moveable troughs can be used to change the configuration of the decking for different coil arrangements.
When the coils are carried with their axes longitudinal to the direction of the car, the coils can move longitudinally in the bed due to acceleration, deceleration, or yard impacts. The interior turns of the coils can also extend or telescope axially out of the coils responsive to the same forces. (In relation to steel coils, xe2x80x9ctelescopexe2x80x9d here means that the inner coils extend out of line with the outer coils. Respecting the sections of a cover, xe2x80x9ctelescopexe2x80x9d means that the covers are shifted to an overlapping relation.) To alleviate these types of longitudinal movement, the prior art has placed transverse bars forward and aft of each coil. However, the weight of a steel coil is so great that the coil or its inner turns may shift longitudinally against the transverse bar. The steel is soft enough that the bar can be impressed on the exposed edges of the coil and even embedded in the coil, preventing the coil from being lifted vertically out of the car. Such engagement of the steel coil with the transverse bar damages or even ruins the metal of the coil.
This problem is discussed in U.S. Pat. No. 3,291,072. Cylindrical objects, such as steel coils, have also been carried transversely in troughs. Each trough has facing, inwardly inclined surfaces that support the coil. The transverse orientation of the coil prevents the inner turns from telescoping and centers the coil on the trough, preventing both forms of shifting. A disadvantage of such troughs is that some or all of the troughs and coils are supported above the center sill or similar structure for handling draft and buff loads. A flatcar does not allow the coils or troughs to project below the center sill of the car.
Well cars which have no center sill, and which transmit longitudinal loads from the couplers and draft sills through side sills, top chords, and other longitudinal members beside or beneath the cargo bed, are known. One example of such well car construction is U.S. Pat. No. 4,841,876. Additionally, U.S. Pat. No. 5,170,717 discloses a well-type car for transporting coils.
The slab car according to the present invention is a 100-125 ton capacity steel flat car for hauling steel slabs with the capacity for hauling steel coils. The car design allows steel slabs of various sizes and weights to be hauled efficiently by placing the slabs longitudinally on the car. The slabs are captive by side stanchions restricting the slabs from lateral movement and bulkheads at the ends preventing longitudinal movement of the slabs. The weight of the slabs is concentrated near the bolsters through raised mounting platforms. The railcar also has the capability to haul steel coils in a built-in trough over the bolster area. The end bulkhead restricts and positions the steel coils allowing the coils in each trough to have an 8xe2x80x3 gap between them for ease of loading and unloading. One end of the car has a built-in cross over platform. The slab side stanchions double as steel coil stanchions restricting the steel coils from unwanted unloading due to coupler forces. The slab car of the present invention provides increased hauling capacity over prior art slab cars with less lineal track space. The loading and unloading of the car is improved over the prior art slab railcars. The ability to alternatively carry steel coils increases the flexibility of the railcar. Finally, the railcar can be easily arranged to specifically suit a specific size of steel slab as well as the diameter and width of steel coil.
A further slab car according to the present invention is a 100 ton flat railcar designed to haul steel slabs. The railcar is designed for 286,000 pound gross rail load. The railcar can accommodate steel slabs between 35xe2x80x3 to 72xe2x80x3 in width and lengths up to 44xe2x80x2.
The advantages of the railcars of the present invention will be clarified in the description of the preferred embodiments together with the figures.